1. Field of the Invention
This invention relates to the discovery that beta-chloro- and beta-bromoethanesulfinic acids and esters can be employed to regulate and/or modify the growth of plants.
2. Description of the Prior Art
Certain of the lower alkyl ethanesulfinate esters which are active in the method of the invention are known compounds. German Pat. No. 2,005,514 discloses the methyl, ethyl and isopropyl esters of 2-chloro- or bromoethanesulfinic acid as anti-cancer agents. The preparation of the tertiary butyl ester of 2-chloroethanesulfinic acid is disclosed in V. S. Etlis et al., Journal General Chemistry U.S.S.R 35, 472-75 (1965). Also, one of the free sulfinic acids useful in the method of the invention, 2-chloroethanesulfinic acid, is disclosed in A. I. Titov and A. N. Baryshnikova, Akad. Nauk., SSR, 157, 681 (1964) and H. Distler, Angew. Chem. Internat. Ed. 4, 300 (1965). However, no reference is known which discloses or suggests the plant growth regulant properties of these known compounds or the class of compounds as a whole which have been found to be active in the process of the invention. Other related art is G. Hesse et al., Chem. Ber. 90, 2106 (1957) which discloses the barium salt of 2-hydroxyethanesulfinic acid and U.S. Pat. No. 2,412,909 which discloses a general reaction wherein unspecified alkyl or substituted alkyl sulfinyl halides may be reacted with alcohols, phenols, etc. to form products which are useful as bleaching agents, dyes, plasticizers and a variety of other uses, but not including plant growth regulators.